The present invention relates to a pressure control valve of fluid, such as hot water or cold water, and more particularly, to an automatic water pressure control valve without a cylinder unit enclosing a water pressure control piston, regulating the quantity of water flow automatically according to the pressure of cold water or hot water. Therefore, production costs of the automatic water pressure control valve is reduced, and heat shock, generated by the sudden rapid change of the water temperature, is prevented.
Generally, at home, a hot water pipe and a cold water pipe of showers in a bathroom or of water injectors in a kitchen are connected between each other. Therefore, when hot water or cold water begins to flow in one place (a kitchen or a bathroom) suddenly, while the mixture of hot water and cold water is flowing in another place (a kitchen or a bathroom), the temperature of the mixed water in another place is changed.
In more detail, when the mixed water of a predetermined temperature is flowing in a bathroom and cold water is supplied to a kitchen suddenly, the temperature of the mixed water in the bathroom rises rapidly. In reverse, when the mixed water of a predetermined temperature is flowing in a bathroom and hot water is supplied to a kitchen suddenly, the temperature of the mixed water in the bathroom drops down rapidly. Most people have such an experience, and in some severe case, people can have “Heat Shock”.
To overcome such problems, Korean Utility Model Patent No. 20-250628 by the same inventor of the present invention discloses an automatic water pressure control valve balancing the temperature of mixed water.
As shown in FIG. 1, the conventional automatic water pressure control valve comprises a main body 510, a cylinder 520, a piston 530, and a cap 540. The main body 510 includes a hot water inlet 511 flowing hot water and a cold water inlet 512 flowing cold water to the main body 510, wherein both water inlets 511 and 512 are bent and adjacent to each other. Furthermore, the main body 510 includes a hot water outlet 513 flowing hot water to the outside and a cold water outlet 514 flowing cold water to the outside from the main body 510.
The cylinder 520, formed between the water inlets 511 and 512 and the water outlets 513 and 514, comprises a first inlet 521 connected with the hot water inlet 511, a second inlet 522 connected with the cold water inlet 512, a first outlet 523 connected with the hot water outlet 513, and a second outlet 524 connected with the cold water outlet 514.
The piston 530 comprises a center cutout 531, a first pressure unit 532, a second pressure unit 533, buffers 534 and 535, a first and second piston holes 536 and 537, a third and fourth piston holes 538 and 539. The center cutout 531 in the inside of the cylinder 520 moves horizontally and interrupts the flow of cold water or hot water. Furthermore, the first pressure unit 532 in one side of the center cutout 531 controls the flow quantity of hot water, and the second pressure unit 533 in the other side of the center cutout 531 controls the flow quantity of cold water. Additionally, a portion of each of the buffers 534 and 535 alleviating the corresponding water pressure is inserted into the corresponding inside of the first and second pressure units 532 and 533. The first and second piston holes 536 and 537 between the center cutout 531 and the first pressure unit 532 are flow paths of hot water, and the third and fourth piston holes 538 and 539 between the center cutout 531 and the second pressure unit 533 are flow paths of cold water.
Furthermore, the cap 540 with two brings 541 and 542 seal the open parts of the main body 510, after the piston 530 is inserted into the cylinder 520.
Additionally, a first cavity 515 is formed in one side of the hot water inlet 511 and a second cavity 516 is formed in one side of the cold water inlet 512 of the main body 510. Similarly, a third cavity 517 is formed in one side of the hot water outlet 513 and a fourth cavity 518 is formed in one side of the cold water outlet 514. Furthermore, the cylinder 520 includes a first cavity hole 525 connected with the first cavity 515, a second cavity hole 526 connected with the second cavity 516, a third cavity hole 527 connected with the third cavity 517, and a fourth cavity hole 528 connected with the fourth cavity 518.
The function of the above described automatic water pressure control valve is illustrated in the following statement.
As shown in FIG. 1, the piston 530 is positioned in the center of the cylinder 520, when the cold water pressure is the same with the hot water pressure. Therefore, hot water flows through the hot water inlet 511 of the main body 510, the first inlet 521 of the cylinder 520, the first and second piston holes 536 and 537 of the piston 530, the first outlet 523 of the cylinder 520, and the hot water outlet 513 of the main body 510, sequentially. Similarly, cold water flows through the cold water inlet 512 of the main body 510, the second inlet 522 of the cylinder 520, the third and fourth piston holes 538 and 539 of the piston 530, the second outlet 524 of the cylinder 520, and the cold water outlet 514 of the main body 510, sequentially. In this case, the size of the first outlet 523 opened by the first pressure unit 532 is the same with the size of the second outlet 524 opened by the second pressure unit 533. Therefore, the quantity of discharged hot water is the same with the quantity of discharged cold water.
Sequentially, when the pressure of cold water rises, the pressure of cold water flowing into the cylinder 520 through the cold water inlet 512 and the second inlet 522 also rises to move the center cutout 531 of the piston 530 to the left direction. Therefore, the first pressure unit 532 of the piston 530 opens the first inlet 523 more widely to enhance the quantity of hot water flow through the hot water outlet 513, and the second pressure unit 533 closes the second inlet 524 almost to reduce the quantity of cold water flow through the cold water outlet 514. As a result, the temperature of the mixed water discharged from a shower or a water injector (not shown) connected with the hot water outlet 513 and the cold water outlet 514 is maintained constantly.
Similarly, when the pressure of hot water rises, the pressure of hot water flowing into the cylinder 520 through the hot water inlet 511 and the first inlet 521 also rises to move the center cutout 531 of the piston 530 to the right direction. Therefore, the second pressure unit 533 of the piston 530 opens the second inlet 524 more widely to enhance the quantity of cold water flow through the cold water outlet 514, and the first pressure unit 532 closes the first inlet 523 almost to reduce the quantity of hot water flow through the hot water outlet 513. As a result, the temperature of the mixed water discharged from a shower or a water injector (not shown) connected with the hot water outlet 513 and the cold water outlet 514 is maintained constantly. As described above, the movement of the piston 530 according to the pressure of hot water and cold water makes the temperature of the mixed water constant.
However, the conventional automatic water pressure control valve balancing the temperature of the mixed water moves the piston 530 within the cylinder 520 after installing the cylinder 520 in the inside of the main body 510. Therefore, the conventional control valve is complicated in structure and comprises many parts to increase production costs.
Furthermore, in the conventional control valve, hot water and cold water has to flow through a complicated flow path including so many parts, such as water inlets 511 and 512 in the man body 510, the first and second inlets 521 and 522 in the cylinder 520, the first and second piston holes 536 and 537 and the third and fourth piston holes 538 and 539 in the piston 530, the first and second outlet 523 and 524 in the cylinder 520, and water outlets 513 and 514 in the main body 510, sequentially. Therefore, the production process of the conventional control valve is too complicated. Furthermore, when water is not flowed, as shown in FIG. 1, the piston 530 within the cylinder 520 should be placed in the center of the main body 510. However, when the water pressure of a water pipe (not shown) connected with the hot water outlet 513 and with the cold water outlet 514 is not constant, backflows from the water pipe makes the piston 530 move into the one direction, left or right. Therefore, in the initial water pressure control states especially, the piston 530 often misses the proper time to balance the temperature of the mixed water.